ElVerde
Posts: 10
Joined: Wed Oct 18, 2017 11:59 am

I want the REX...do I need it?

Wed Oct 18, 2017 12:19 pm

I had a kid, sold my 911, and am trying to figure out what to buy. I don't want to spend a ton of money on some luxo-thing, but I like driving something somewhat unique. I would have kept the 911 if it weren't for wanting to hang out w/ my 7 month old, and it's hard to be satisfied with any other sports car after owning a 911...especially one w/ 4 doors.

I drive about 9 miles a day to and from work. My wife has a 2014 328xi wagon that we can use for longer trips. Obviously I don't need the REX, but I think I like the flexibility of having it if needed, if I take a work-role that requires more driving, etc.

Is there any appreciable maintenance cost difference/reliability concerns of REX vs non-REX?

Also, will a german shepherd fit in the back?

I'm thinking I will likely buy a used i3 rather than lease a new one...seems like a better value prop. Anything to be scared of buying one CPO?

ElVerde
Posts: 10
Joined: Wed Oct 18, 2017 11:59 am

Re: I want the REX...do I need it?

Wed Oct 18, 2017 12:21 pm

Oh and also...any concerns with just plugging it into the wall at home? I drive so little I figure it will be fine; I don't want to install a charger because I rent and could move anytime.

Milam
Gold Member
Posts: 71
Joined: Tue Jun 20, 2017 4:03 pm

Re: I want the REX...do I need it?

Wed Oct 18, 2017 12:57 pm

I have a 2017 REX with the large battery.

I have never needed my REX.
I always have enough battery for my uses.
I have had two problems with my REX, both minor.

If I had to do it over again, I would not get the REX.

Tried FAST DC Charging last night the first time.
Pretty slick, worked great. Added 20% in the time it took to use the restroom and get a drink.

Level 2 chargers work great.

But many times, I just use a Level 1 charger and it works great.

The car definitely works great.

I almost never drive my Touareg Diesel anymore.

Tom Milam

ElVerde
Posts: 10
Joined: Wed Oct 18, 2017 11:59 am

Re: I want the REX...do I need it?

Wed Oct 18, 2017 1:07 pm

Thank you for the quick reply!

So...no long term issues or extra battery degradation from plugging it into the wall?

jadnashuanh
Posts: 3500
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: I want the REX...do I need it?

Wed Oct 18, 2017 2:29 pm

ElVerde wrote:Thank you for the quick reply!

So...no long term issues or extra battery degradation from plugging it into the wall?


It's possible, but unproven, that the EVSE that comes with the car in the USA (level 1, 120vac device) maybe easier on the batteries. But, nobody has reported problems with theirs using higher capacity units, and some have quite high mileages on them. IOW, not a big deal.

Consider, though, that if you did discharge the battery fully, and wanted to use your device that comes with the car, it could take more than a day to refill it. Also, if it gets cold, and you want to maximize your range (shouldn't be an issue with your stated commute), the level 1 device, even when you started with a full battery, if you tell it to set a departure time and precondition the cabin, could lose some charge...the thing isn't big enough to cover prewarming the batteries and preconditioning the cabin. I've seen mine pull 20A during this process, which is nearly twice what the level 1 device can provide. But, at your daily average use, it would easily recharge overnight with lots of time to spare.

FWIW, you'll use a slight bit more electricity to recharge the car using a 120vac device...the car needs to make about 380vdc to charge its batteries...starting with a lower voltage input is less efficient by maybe 5-10% than starting with 240vac. There are a bunch of level 2 EVSEs out there that can be purchased with a plug on them, but you'd still need to wire up a socket. If you did sell the house, having that socket might actually be a selling point as EVs become more and more prevalent. Depending on how far the wiring had to be run, it may not be a very big investment, and portable EVSEs come in all sorts of flavors and sizes, some of them are 120/240 capable. A 240vac device pulling the same amps is twice as fast as one on 120 (P=V*A power=volts*amps).

While maintenance is covered by the warranty in the beginning, consider that having the REx includes all of the issues with any ICE:
- muffler
- gas tank
- spark plugs
- oil changes
- filter changes (all have a cabin filter, but the engine needs air and oil filters, too)
- heavier and therefore slightly less efficient because of the extra weight
- more complex

Since the REx may not come on that often or run all that long depending on needs, the muffler might not last as long as on an ICE where things always got warm enough to purge it of moisture and condensation...just a general concern, not evidenced (yet) on the i3 REx.
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV

Milam
Gold Member
Posts: 71
Joined: Tue Jun 20, 2017 4:03 pm

Re: I want the REX...do I need it?

Wed Oct 18, 2017 2:40 pm

After thinking it over.

I would recommend that you get an used i3 without the REX.
The REX units are easy to use and live with. Would depend
upon the price. I have never needed mine. It is nice
knowing that it is available if needed.

If you do get one, code your i3. So that you can use it at 75%.
It would make me nervous to wait until it was at 8% level.

You can always rent a car for family trips.

A German Shepard will fit in the back seat comfortably.

I sold a Cirrus SR22 TN and leased an i3.

Can you buy one with the BMW CPO?

I am about to buy an used BMW X5 with the CPO.
This will be our fourth BMW. Would rather pay
for repairs up front, than later. I will sleep better
at night.

Tom

Good luck.
Let us know what you do and how it works out.

justanotherdrunk
Posts: 265
Joined: Thu Feb 19, 2015 9:56 am
Location: Silicon Valley

Re: I want the REX...do I need it?

Wed Oct 18, 2017 2:52 pm

the rex was worthless during the 2 years i leased it

just bought a cpo bev a few weeks ago for a stupid cheap price ... very happy with it so far

i only charge in the garage L1 120V reduced ~8A because like you i dont drive far and dont care about longer charging times

L1 max ~14A almost caused a fire in my garage so be aware

the i3 is a superb daily driver city car for lots of relatively short trips ... 95% of my driving

for the 5% when i need to go far i take the toyota
2014 i3 BEV
Solar Orange/ Mega

ElVerde
Posts: 10
Joined: Wed Oct 18, 2017 11:59 am

Re: I want the REX...do I need it?

Wed Oct 18, 2017 3:26 pm

For Clarity: I am renting the house...that's why I don't want to install it.

I have a 2014 328xi wagon for longer trips...wife doesn't work.

The German Shepherd is going ALL THE WAY in the back, not in the backseat :)

The more I research, the more the all-electric makes more sense.

So now the question is....lease or buy a 14/15? Lease looks like 300ish/mo whereas buying would be writing a check for 18k or so...is 30 more miles of range really worth it???

I'm really pissed because last month the local utility here in San Diego was offering an ADDITIONAL 10k off of these things...I missed out.

jadnashuanh
Posts: 3500
Joined: Thu May 22, 2014 2:07 pm
Location: Nashua, NH USA

Re: I want the REX...do I need it?

Wed Oct 18, 2017 5:48 pm

Only you can decide about lease/buy. If you plan to keep the car a long time, buy has its advantages. If you like to change your cars on a regular basis, lease has its advantages (one of which is constant warranty coverage). But, after infant mortality, a BEV should be quite reliable, and the battery warranty is 8-years, or 100K miles.

I saw no big up side to buying a REx for my use pattern. I would probably be better off selling my ICE and maybe renting one when needed, but it's paid for, so mostly just insurance costs (but I only have a one-car garage, which means the i3 sits outside - not as nice in the winter!).

As battery tech improves, and more EVs are out there, range anxiety will wane somewhat. More than one forum member has said they essentially never use the REx, so, to me at least, it seems a waste to carry around - it still needs servicing, even if not used. The BEV has a heat pump verses the REx's resistance heating (like a toaster), so when heating is required, the REx will not be as efficient. Only when it is super cold and the heat pump can't provide the needed heat does the BEV resort to the resistance heating. If your commute was longer, or you needed or wanted to sell the car in a few years, having the larger battery pack would be better and easier to sell down the road. But, the vast majority of people use the car as intended...to commute or run around the city, and even the original i3 has more than enough capacity for that. Plus, as CCS charging starts to show up more places, and can be relied on to be available when needed, the size of the battery is even less important.
Jim DeBruycker
2011 535i x-drive GT, 2014 i3 BEV

alohart
Posts: 963
Joined: Sat Nov 01, 2014 7:36 pm
Location: Honolulu, HI

Re: I want the REX...do I need it?

Wed Oct 18, 2017 6:55 pm

ElVerde wrote:So...no long term issues or extra battery degradation from plugging it into the wall?

The Occasional Use Cables (OUC) included with some i3's were 10 A units while others were 12 A. A basic 120 V outlet is rated for 15 A, but only 80% of that, or 12 A, for continuous use as when charging an EV. Some EV owners have had problems with old outlets that overheated at 12 A. The i3's iDrive system allows the maximum charging current to be reduced from the Maximum if necessary, but of course, that would increase the charging time. It would be best to monitor the OUC plug and outlet the first few times charging at the Maximum setting to insure that overheating isn't a problem or that other loads on the same circuit don't overload the circuit and trip the circuit breaker. Nevertheless, with your anticipated use pattern, charging with the OUC should be sufficient, even if you had to reduce the charging current.
Aloha,
Art

2014 BMW i3 Arravani Grey, Giga World, Tech + Driving Assist, Parking Assist, DC Fast Charging, JuiceBox EVSE

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